The present invention relates to a device for the vibration-absorbing mounting of a compressed-air generator on a mounting support of a rail vehicle having a self-supporting structure, which has a first spring element fastened to the mounting support.
Compressed-air generators generate the compressed air required for the operation of a compressed-air brake and other pneumatic devices in rail vehicles. Single-stage or multiple-stage piston-type air compressors, depending on the construction, in addition to generating forces due to gravity and moments of inertia, also generate tangential forces. So far, an insulation of the above-mentioned forces or moments in the horizontal or vertical direction had taken place by the arrangement of elastic mounting devices of the same type on the vehicle structure. The elastic mounting devices consist of a spring element, particularly a rubber spring. However, in view of modern light construction methods in rail vehicle construction with self-supporting structures made of thin sheet metal and aluminum, the demands made on the vibration insulation of the rail vehicle are no longer met by the above-mentioned mounting device. In the case of lightweight understructures, the degree of insulation of conventional mounting devices is insufficient where construction-caused resonances occur on the understructure side.
In view of the above, it is an object of the invention to provide a device for the vibration-absorbing mounting of a compressed-air generator on a mounting support of a rail vehicle, in the case of which a better insulating effect is achieved without considerably increasing the lateral and longitudinal deflections of the compressed-air generator.
This invention is achieved by means of the present invention.
The invention is surprisingly based on the recognition that three conditions must exist for achieving the object to be obtained: First, a second spring element should be provided on which the compressed-air generator is arranged. The second spring element or the first spring element should also have a spring rigidity essentially in the vertical direction which is no more than half as large as its rigidity essentially in the horizontal direction. Finally, the first spring element and the second spring element should be connected in series. This device achieves not only a vibration insulation or vibration absorption which by far exceeds anything known from the prior art, but also avoids that the longitudinal and lateral deflections of the compressed-air system are considerably enlarged during the operation. Measurements have indicated that the acceleration of an understructure of a rail vehicle could be reduced to up to 30% of the values known from the prior art if the first spring element is a rubber element or a rubber composite element and the second spring element is a wire rope spring.
Advantageously, the first spring element and the second spring element can be connected with one another by means of a connection element. This ensures a simple construction of the device according to the invention. In a particularly advantageous manner, the connection element is constructed as a traverse or an adapter plate which act as a damping mass. By means of a variation of the mass of the connection element or of the traverse or of the adapter plate, an additional damping influence on a self-supporting structure equipped with the device according to the invention can be achieved.